重复最后一个附件

Question

我正在尝试使用python smtp库发送电子邮件。一切似乎工作正常，但我正在重复最后一个附件，同时尝试发送两个附件我最后重复三个。我想弄清楚这个但是不能。这是我的消息编写功能的代码片段：

def create_email_message(sender_address, recipient_address, subject, body, filesin=[]):
    '''
    Creates a ready to go email message along with the headers.
    @param: filesin
            A list of tuples. Example:
            [(file1_name,file1_data),(file2_name,file2_data),.......]
    '''

    msg = MIMEMultipart('alternative')
    msg['Subject'] = "%s" % Header(subject, 'utf-8')
    msg['From'] = sender_address
    msg['To'] = recipient_address

    htmlpart = MIMEText(body, 'html', 'UTF-8')
    msg.attach(htmlpart)


    for file_obj in filesin:
        data = file_obj[1]
        name = file_obj[0]
        attach_obj = MIMEBase("application", "octet-stream")
        attach_obj.set_payload(data)
        Encoders.encode_base64(attach_obj)
        attach_obj.add_header('Content-Disposition', 'attachment',
                              filename=name)
        msg.attach(attach_obj)

    return msg.as_string() 

filesin 参数是一个元组，如函数定义所示。最奇怪的部分是，当我查看原始电子邮件时，gmail只显示两个内容处置标题。无法弄清楚最后一个附件重复的原因。

问候。